Coriolis and impact wear testers are commonly used in the slurry industry to determine the sliding and impact wear coefficients (respectively) for a given combination of slurry and wear substrate material. In these experiments, the mass loss of wear specimens, and the easily-measured bulk concentration, flow rate and angle of the impact wedge are correlated to determine estimates of wear coefficients. In CFD-based wear prediction in slurry pump casings and impellers, these experimentally determined coefficients are used in combination with such near-wall computed quantities as particle concentration, velocity, and angle of impact, with a potential inconsistency between the bulk quantities of the wear experiments and the local CFD-based flow field.
This paper uses finite element CFD to obtain the slurry flow field in the Coriolis and impact wear testers. The ratio of the wear-related bulk quantities to the local quantities is evaluated for both impact and sliding wear. It is observed that this ratio for the impact wear coefficient is of the order of 2.0 for the flow conditions studied. In the Coriolis wear tester experiment, it turns out fortuitously that for certain operating conditions, the wear coefficient determined using bulk flow quantities would be nearly the same as the wear coefficient determined using local quantities.